Diphenylamino and indolyl substituted pyromellitides

ABSTRACT

This invention relates to 3,7-bis(disubstituted aminophenyl- or indolyl)-3,7-bis(diphenylamino)pyromellitides, 3,5-bis(disubstituted aminophenyl- or indolyl)-3,5-bis(diphenylamino)pyromellitides and mixtures thereof useful as color formers, particularly in carbonless duplicating and thermal marking systems, which are prepared by the interaction of 2,5-bis(disubstituted aminophenyl- or indolyl)carbonyl-1,4-benzenedicarboxylic acids or 2,4-bis(disubstituted aminophenyl- or indolyl)carbonyl-1,5-benzenedicarboxylic acids and mixtures thereof with diphenylamines.

CROSS REFERENCE TO PRIOR APPLICATIONS

This application is a division of copending application Ser. No.182,717, filed Aug. 29, 1980 now U.S. Pat. No. 4,343,493.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

This invention relates to novel compounds classified in the field oforganic chemistry as 3,7-bis[4-(disubstituted amino)phenyl]- or(indol-3-yl)-3,7-bis(diphenylamino)pyromellitides and3,5-bis[4-(disubstituted amino)phenyl]- or(indol-3-yl)-3,5-bis(diphenylamino)pyromellitides and mixtures thereofuseful as color precursors, particularly in the art of carbonlessduplicating, for example, pressure-sensitive and thermal markingsystems; to processes for preparing the pyromellitides; and topressure-sensitive and thermal marking systems containing thepyromellitides.

(b) Description of the Prior Art

Several classes of organic compounds of widely diverse structural typesare known to be useful as colorless precursors for carbonlessduplicating systems. Among the more important classes, there may benamed phenothiazines, for example, benzoyl leuco methylene blue;phthalides, for example, crystal violet lactone; fluorans, for example,2'-anilino-6'-diethylaminofluoran and2'-dibenzylamino-6'-diethylaminofluoran; and various other types ofcolorless precursors currently employed in commercially acceptedcarbonless copy systems. Typical of the many such systems taught in theprior art are those described in U.S. Pat. Nos. 2,712,507, 2,800,457 and3,041,289 which issued July 5, 1955, July 23, 1957 and June 26, 1962,respectively. Many of the color formers in the prior art suffer one ormore disadvantages such as low tinctorial strength, poor lightstability, low resistance to sublimation, low susceptibility tocopiability of the color-developed form in standard copying machines,for example, a Xerox® copier, and low solubility of common organicsolvents, the last-mentioned disadvantage thus requiring the use ofspecialized and expensive solvents in order to obtain microencapsulatedsolutions of sufficient concentration for use in pressure-sensitivecopying machines.

The following items to date appear to constitute the most relevant priorart with regard to the instant invention.

U.S. Pat. No. 3,268,537, issued Aug. 23, 1966, discloses and claims amixture of two isomeric pyromellitides, individually of the formulas##STR1## in which the Xs are selected from the group consisting of9-julolidinyl, 4-aminophenyl and mono- and disubstituted 4-aminophenylmoieties. The compounds are disclosed to be colorless when dissolved insolvents normally used in carbonless duplicating systems and developdark-colored images upon contact with suitable color-developingsubstances, for example, an acidic clay. The pyromellitides of thispatent are prepared through the intermediates2,5-[bis(4-dialkylaminophenyl)carbonyl]-1,4-benzenedicarboxylic acid and2,4-[bis(4-dialkylaminophenyl)carbonyl]-1,5-benzenedicarboxylic acid,respectively.

U.S. Pat. No. 3,491,117, issued Jan. 20, 1970, discloses and claims achromogenic pyromellitide selected from the group consisting of:##STR2## and mixtures thereof, where R₁, R₂, R₃ and R₄ consist of1,2-dialkylindol-3-yl and p-dialkylaminophenyl groups wherein alkyl hasless than five carbon atoms, such that as least two indolyl radicals arepresent in a cis relationship in compounds having a cis configurationand in a trans relationship in compounds having a trans configuration.The chromogenic compounds are disclosed as being useful inpressure-sensitive recording systems. The pyromellitides disclosed inthis patent are prepared through 2,4-[bis(4-dialkylaminophenyl-, orindolyl)carbonyl]-1,5-benzenedicarboxylic acid and2,5-[bis(4-dialkylaminophenyl-, orindolyl)carbonyl]-1,4-benzenedicarboxylic acid, respectively.

Fawcett, Cassidy and Lin in the Journal of Organic Chemistry 42 (17),2929-2930 (1977) describe the preparation and physical characteristicsof 3,3,5,5-tetraphenylpyromellitide and 3,3,7,7-tetraphenylpyromellitidefrom the interaction of 4,6-dibenzoylisophthalic acid or2,5-dibenzoylterephthalic acid and benzene in the presence of aluminumchloride. No indication of utility for the compounds is given in thearticle.

Belgian Pat. No. 862,217, published June 22, 1978, which correspondsessentially to U.S. Pat. No. 4,168,378 and 4,182,714 which issued Sept.18, 1979 and Jan. 8, 1980, respectively, in the names of Paul JosephSchmidt and William Mo-Wei Hung, the inventors in the instantapplication, discloses a series of phthalides useful as color formers inpressure-sensitive carbonless duplicating systems, thermal markingsystems and hectographic or spirit-reproducing copying systems andhaving the formula ##STR3## wherein Q is di-lower-alkylamino, nitro,halo or COX, where X is hydroxyl, benzyloxy, alkoxy having from 1 to 18carbon atoms or OM where M is an alkali metal cation, an ammonium cationor a mono-, di- or tri-alkylammonium cation having from 1 to 18 carbonatoms; n is 0; or 1 when Q is di-lower-alkylamino, nitro or COX; or from1 to 4 when Q is halo; Y₁, Y₂, Y₃ and Y₄ are the same or different andare hydrogen, halo, hydroxyl, lower-alkoxy, alkyl having from 1 to 9carbon atoms, phenyl-lower-alkyl, COOR₄ or NR₅ R₆, where R₄ and R₅ arehydrogen or lower-alkyl and R₆ is hydrogen, lower-alkyl, cycloalkylhaving from 5 to 7 carbon atoms or lower alkanoyl; Z is chosen from thegroup consisting of ##STR4## and 9-julolidinyl in which R is hydrogen ornon-tertiary alkyl having from 1 to 4 carbon atoms; R₁ is hydrogen ornon-tertiary alkyl having from 1 to 18 carbon atoms; R₂ is hydrogen,phenyl or non-tertiary alkyl having from 1 to 4 carbon atoms; R₃ ishydrogen, non-tertiary alkyl having from 1 to 4 carbon atoms ornon-tertiary alkoxy having from 1 to 4 carbon atoms; R₇ is hydrogen,halo, lower-alkyl lower-alkoxy or di-lower-alkylamino; R₈ islower-alkyl; and R₉ is lower-alkyl, benzyl, phenyl or phenyl substitutedwith a lower-alkyl or lower-alkoxy group.

SUMMARY OF THE INVENTION

The present invention in its composition of matter aspect, provides fornovel pyromellitides selected from the group consisting of3,7-bis(Y)-3,7-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitides, 3,5-bis(Y)-3,5-bis[N-(R, R^(o)-phenyl)-N-(R¹, R² -phenyl)amino]pyromellitides, and mixtures thereofwhich are useful as color formers in pressure-sensitive duplicatingsystems and in thermal marking systems. The compounds have enhancedsolubility in common organic solvents and develop colored images of goodto excellent tinctorial strength which have good light stability.

In its process aspect, the invention relates to a process for preparinga series of pyromellitides selected from the group consisting of3,7-bis(Y)-3,7-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide and 3,5-bis(Y)-3,5-bis-[N-(R, R^(o)-phenyl)-N-(R¹, R² -phenyl)amino]pyromellitide and mixtures thereofwhich comprises interacting an appropriate2,5-bis(Y)-carbonyl-1,4-benzenedicarboxylic acid and2,4-bis(Y)-carbonyl-1,5-benzenedicarboxylic acid, respectively andmixtures thereof with a N-(R, R^(o) -phenyl)-N-(R¹, R² -phenyl)amine inthe presence of an anhydride of an alkanoic acid.

The present invention provides in its articles of manufacture aspect,pressure-sensitive carbonless duplicating systems and thermal markingsystems each containing at least one color-forming substance comprisinga pyromellitide selected from the group consisting of3,7-bis(Y)-3,7-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide and 3,5-bis(Y)-3,5-bis[N-(R, R^(o)-phenyl)-N-(R¹, R² -phenyl)amino]pyromellitide and mixtures thereof.

DETAILED DESCRIPTION INCLUSIVE OF THE PREFERRED EMBODIMENTS

More specifically, this invention in its composition of matter aspect,resides in the novel pyromellitides, which are particularly useful ascolorless precursors in the art of carbonless duplicating and thermalmarking, and which are selected from the group consisting of3,7-bis(Y)-3,7-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide of the formula ##STR5## and3,5-bis(Y)-3,5-bis-[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)-amino]pyromellitide of the formula ##STR6## and mixturesthereof wherein R, R^(o), R¹ and R² are the same or different and areselected from the group consisting of hydrogen, halo, hydroxyl,non-tertiary C₁ to C₄ alkoxy, non-tertiary C₁ to C₉ alkyl, COOZ and NZ¹Z² where Z and Z¹ are hydrogen or non-tertiary C₁ to C₄ alkyl and Z² ishydrogen, non-tertiary C₁ to C₄ alkyl, C₅ to C₇ cycloalkyl, C₁ to C₄alkanoyl, phenylsulfonyl or phenylsulfonyl substituted by non-tertiaryC₁ to C₄ alkyl; Y is a radical selected from the group consisting of##STR7## in which R³ and R⁴ are the same or different and are selectedfrom the group consisting of non-tertiary C₁ to C₄ alkyl, benzyl andbenzyl substituted by one or two of halo, C₁ to C₄ alkyl, C₁ to C₄alkoxy or nitro; R⁵ is selected from the group consisting of hydrogen,halo and non-tertiary C₁ to C₄ alkyl and non-tertiary C₁ to C₄ alkoxy;R⁶ is selected from the group consisting of hydrogen and non-tertiary C₁to C₁₂ alkyl; and R⁷ is selected from the group consisting of hydrogen,non-tertiary C₁ to C₄ alkyl and phenyl.

In a first particular embodiment in accordance with its composition ofmatter aspect, the invention sought to be patented resides in the novelpyromellitides selected from the group consisting of 3,7-bis(1-R⁶ -2-R⁷-indol-3-yl)-3,7-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitides and 3,5-bis(1-R⁶ -2-R⁷-indol-3-yl)-3,5-[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]-pyromellitides according to Formulas I and II andmixtures thereof wherein Y represents 1-R⁶ -2-R⁷ -indol-3-yl and R,R^(o), R¹, R², R⁶ and R⁷ each have the same respective meanings given inFormulas I and II.

In a second particular embodiment in accordance with its composition ofmatter aspect, the invention sought to be patented resides in the novelpyromellitides selected from the group consisting of 3,7-bis(2-R⁵ -4-NR³R⁴ -phenyl)-3,7-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide and 3,5-bis(2-R⁵ -4-NR³ R⁴-phenyl)-3,5-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide according to Formulas I and II and mixturesthereof wherein Y represents 2-R⁵ -4-NR³ R⁴ -phenyl and R, R^(o), R¹,R², R³, R⁴ and R⁵ each have the same respective meanings given inrelation to Formulas I and II.

In its process aspect, the invention sought to be patented resides inthe process for preparing pyromellitides selected from the groupconsisting of 3,7-bis(Y)-3,7-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide and 3,5-bis(Y)-3,5-bis[N-(R, R^(o)-phenyl)-N-(R¹, R² -phenyl)amino]pyromellitide and mixtures thereofwhich comprises interacting an appropriate2,5-bis(Y)carbonyl-1,4-benzenedicarboxylic acid, and2,4-bis(Y)carbonyl-1,5-benzenedicarboxylic acid, respectively andmixtures thereof having the respective formulas ##STR8## with adiarylamine having the formula ##STR9## in the presence of the anhydrideof an alkanoic acid having from 2 to 5 carbon atoms wherein R, R^(o),R¹, R² and Y each have the same meanings given in relation to Formulas Iand II.

In an article of manufacture aspect, the invention sought to be patentedresides in a pressure-sensitive or thermal marking system comprising asupport sheet coated with a layer containing as a color-formingsubstance a pyromellitide selected from the group consisting of3,7-bis(Y)-3,7-bis[N-(R, R°-phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide and 3,5-bis(Y)-3,5-bis[N-(R,R°-phenyl)-N-(R¹, R² -phenyl)amino]pyromellitide and mixtures thereofaccording to Formulas I and II wherein R, R°, R¹, R² and Y each have thesame respective meanings given relative to Formulas I and II.

In a particular embodiment in accordance with its article of manufactureaspect, the invention sought to be patented resides in apressure-sensitive transfer sheet, adapted for use with a receivingsheet having an electron accepting layer, comprising a support sheetcoated on one side with a layer of pressure-rupturable microcapsules;said microcapsules containing a liquid solution of a color-formingsubstance comprising at least one compound having Formula I or II.

Another embodiment in accordance with its article of manufacture aspect,resides in a heat responsive record material comprising a support sheetcoated on one side with a layer containing a mixture comprising at leastone color-forming compound having Formula I or II and an acidicdeveloper arranged such that application of heat will produce amark-forming reaction between the color-forming compound and the acidicdeveloper.

As used herein the term "non-tertiary C₁ to C₄ alkyl", denotes saturatedmonovalent straight or branched aliphatic hydrocarbon radicals includingmethyl, ethyl, propyl, isopropyl, butyl, isobutyl, and the like.Further, the term "non-tertiary C₁ to C₉ alkyl" as used herein includesin addition to the aliphatic hydrocarbon radicals defined as C₁ to C₄alkyl above, amyl, 1-methylbutyl, 3-methylbutyl, hexyl, isohexyl,heptyl, isoheptyl, octyl, isooctyl, 2-ethylhexyl, nonyl, 3-ethylheptyl,and the like. The term "non-tertiary C₁ to C₁₂ alkyl" as used hereinincludes the terms "non-tertiary C₁ to C₄ alkyl" and "non-tertiary C₁ toC₉ alkyl" as defined above, as well an n-decyl, n-undecyl, n-dodecyl,and the like.

As used herein the term "halo" includes chloro, fluoro, bromo and iodo.Chloro is the preferred halo substituent because of the relatively lowcost and ease of preparation of the required chloro-substitutedintermediates and because the other halogens offer no particularadvantages over chloro. However the other above-named halo substituentsare also satisfactory.

As used herein the term "cycloalkyl having from 5 to 7 carbon atoms"includes cyclopentyl, cyclohexyl and cycloheptyl.

The term "C₁ to C₄ alkanoyl" denotes saturated acyclic acyl groupshaving from 1 to 4 carbon atoms which may be straight or branched asexemplified by formyl, acetyl, propionyl, butyryl, isobutyryl, and thelike.

The term "non-tertiary C₁ to C₄ " alkoxy includes saturated, acyclic,straight or branch-chained groups such as methoxy, ethoxy, propoxy,isopropoxy butoxy, sec-butoxy and isobutoxy.

The novel compounds of Formulas I and II hereinabove are essentiallycolorless in the depicted form. When contacted with an acidic medium,for example, silica gel or one of the type ordinarily employed inpressure-sensitive carbonless duplicating systems such as silton clay orphenolic resins, the compounds of Formulas I and II develop a red-orangeto an orange-colored image of good to excellent tinctorial strength, andpossess an enhanced light stability over the prior art compounds,excellent xerographic copiability, and good resistance to sublimation.The compounds are thus highly suitable for use as colorless precursors,that is color-forming substances in pressure-sensitive carbonlessduplicating systems. The red-orange to orange image developing colorformers can be used alone or as toners in admixture with other colorformers to produce developed images of a neutral shade which desirablyare readily copiable by xerographic means. Moreover, the compounds ofFormulas I and II have enhanced solubility over the prior art compoundsin common and inexpensive organic solvents such as odorless mineralspirits, kerosene, vegetable oils and the like thereby avoiding the needfor more expensive specialized solvents such as polyhalogenated oralkylated biphenyls which have ordinarily been used to preparemicroencapsulated solutions of the color formers of the prior art.

The compounds of this invention may be incorporated in any of thecommercially accepted systems known in the carbonless duplicating art. Atypical technique for such application is as follows. Solutionscontaining one or more colorless precursor compounds of Formulas I andII, optionally in admixture with other color formers, in suitablesolvents are microencapsulated by well-known procedures, for example, asdescribed in U.S. Pat. No. 3,649,649. The microcapsules are coated onthe reverse side of a transfer sheet with the aid of a suitable binderand the coated transfer sheet is then assembled in a manifold with themicrocapsule coated side in contact with a receiving sheet coated withan electron accepting substance, for example, silton clay or phenolicresin. Application of pressure to the manifold such as that exerted by astylus, typewriter or other form of writing or printing causes thecapsules on the reverse side to rupture. The solution of the colorformer released from the ruptured microcapsules flows to the receivingsheet and on contact with the acidic medium thereon forms red-orange toorange-colored images of good tinctorial strength. It is, of course,obvious that variants of this mode of application can be utilized. Forexample, the receiving sheet in a manifold can alternatively be coatedwith the subject compounds and the acidic developing agent can becontained in microcapsules applied to the reverse side of the top sheetin the manifold; or the receiving sheet can be coated with a mixturecontaining both the acidic developing agent and the microencapsulatedcolor former.

It has also been found that when the compounds of Formulas I and II areintimately mixed with an acidic developer of the type generally employedin thermal papers such as described in U.S. Pat. No. 3,539,375, that is,papers which produce a colored image when contacted with a heated stylusor heated type, for example, bisphenol A, heating of the mixtureproduces a colored image of varying shades from red-orange to orangedepending on the particular compound of the invention employed. Theability of the compounds of Formulas I and II to form a deep color whenheated in admixture with an acidic developer such as bisphenol A, makesthem useful in thermal paper marking systems, either where an originalor a duplicate copy is prepared by contacting the thermal paper with aheated stylus or heated type in any of the methods generally known inthe art.

The best mode contemplated by the inventors of carrying out thisinvention will now be described so as to enable any person skilled inthe art to which it pertains to make and use the same.

In accordance with the process aspect of this invention the3,7-bis(Y)-3,7-bis[N-(R, R°-phenyl)-N-(R¹, R²-phenyl)amino]pyromellitides of Formula I and 3,5-bis(Y)-3,5-bis-[N-(R,R°-phenyl)-N-(R¹, R² -phenyl)amino]pyromellitides of Formula II andmixtures thereof are obtained by interacting in approximatelyequimolecular proportions an appropriate benzenedicarboxylic acid,2,5-bis[(Y)-carbonyl]-1,4-benzenedicarboxylic acid of Formula III,2,4-bis[(Y)-carbonyl]-1,5-benzenedicarboxylic acid of Formula IV ormixtures thereof with an appropriate N-(R, R°-phenyl)-N-(R¹, R²-phenyl)amine of Formula V. The reaction is conveniently carried out ina dehydrating solvent, for example, an anhydride of a C₂ to C₅ alkanoicacid such as acetic anhydride at a temperature in the approximate rangeof 20°-60° C. for from approximately thirty minutes to forty-eighthours. The pyromellitides thus obtained can be isolated by severalmethods. One such method of isolation is to filter the pyromellitidesfrom the reaction mixture if they are insoluble. An alternative methodof isolation is to pour the reaction mixture into a miscible non-solventfor the product, for example, water or an alcohol such as isopropylalcohol and filter the pyromellitides from the mixture. Thepyromellitides, once isolated, can be purified by conventional meanssuch as trituration or recrystallization from a suitable solvent. Theisomeric mixtures of pyromellitides can, if desired, be separated byconventional means such as fractional crystallization or chromatographyor simply and preferably used as mixtures in the practice of thisinvention.

The requisite bis(Y)carbonylbenzenedicarboxylic acids,2,5-bis(Y)carbonyl-1,4-benzenedicarboxylic acid and2,4-bis(Y)carbonyl-1,5-benzenedicarboxylic acid and mixtures thereof ofFormulas III and IV required in the practice of this invention areconveniently prepared by the interaction of pyromellitic dianhydridewith approximately two molecular proportions of a 1-R⁶ -2-R⁷ -indole ora 3-R⁵ -N-R³ -N-R⁴ -aniline wherein R³, R⁴, R⁵, R⁶, R⁷ and Y each havethe same meanings given in relation to Formulas III and IV. The reactionis usually carried out in the presence of a Lewis acid, for example,aluminum chloride, and with a diluent such as benzene, toluene orchlorobenzene at a temperature in the range of 0°-65° C. Alternatively,when indoles are interacted with pyromellitic anhydride, it is notnecessary to use a Lewis acid and the reaction can be carried out in aC₂ to C₅ alkanoic acid, for example, acetic acid, and the productisolated by filtration. When a Lewis acid is used, thebis(Y)carbonylbenzenedicarboxylic acids are isolated by adding dilutemineral acid, for example, hydrochloric acid to the reaction mixture,filtering off the insoluble benzenedicarboxylic acid product, andwashing the filter cake with water. The product is dissolved in a diluteaqueous alkali solution, treated with decolorizing charcoal andclarified. The dilute alkali solution of the product is made acid by theaddition of a mineral acid, for example, hydrochloric acid and thebenzenedicarboxylic acid product collected by filtration. The productmay be purified by conventional means but is generally dried and used asis.

It will, of course, be appreciated that reaction of pyromelliticdianhydride with an indole or a N,N-dialkylaniline can produce isomersof a mixture of isomers of bis(indolyl- ordialkylaminophenyl)carbonylbenzenedicarboxylic acids. For example,reaction of pyromellitic dianhydride with indole can product a mixtureof 2,4-bis(indolyl)carbonyl-1,5-benzenedicarboxylic acid and2,5-bis(indolyl)carbonyl-1,4-benzenedicarboxylic acid. Similarly,reaction of pyromellitic anhydride with a N,N-dialkylaniline can producean isomeric mixture ofbis(dialkylaminophenyl)carbonylbenzenedicarboxylic acids. These mixturesof isomeric bis(indolyl- ordialkylaminophenyl)carbonylbenzenedicarboxylic acids can be separated byconventional means such as fractional crystallization or chromatography.Alternatively, the isomeric mixtures can be reacted directly withappropriate N-(R, R°-phenyl)-N-(R¹, R² -phenyl)amines to produceisomeric mixtures of pyromellitides of Formulas I and II. Thus, reactionof a mixture of 2,5-bis(indolyl- ordialkylaminophenyl)carbonyl-1,4-benzenedicarboxylic acid and2,4-bis(indolyl- or dialkylaminophenyl)carbonyl-1,5-benzenedicarboxylicacid with N-(R, R°-phenyl)-N-(R¹, R² -phenyl)amine will produce amixture of the corresponding 3,7- and 3,5-bis(indolyl- ordialkylaminophenyl)-3,7- and 3,5-bis(diphenylamino)pyromellitides. Themixtures of pyromellitides can, if desired, be separated by conventionalmeans or simply and preferably used as mixtures in the practice of thisinvention.

Indole and the substituted indoles required as intermediates of thecarbonylbenzenedicarboxylic acid intermediates of Formulas III and IVwherein Y represents indolyl, form an old and well-known class ofcompounds which are readily obtained by conventional procedures wellknown in the art. The following compounds are exemplary of indolesuseful in the practice of this invention.

Indole,

1-Methylindole,

2-Methylindole,

1,2-Dimethylindole,

1-Ethyl-2-methylindole,

1-Propyl-2-methylindole,

1-Butyl-2-methylindole,

1-Octyl-2-methylindole,

2-Ethylindole,

2-Ethyl-1-methylindole,

1-Isopropylindole,

2-Isopropylindole,

1-Isobutyl-2-methylindole,

1-Hexylindole,

2-Propylindole,

1-Isoamylindole and

1-(2-Ethylhexyl)-2-methylindole.

The 3-R⁵ -N-R³ -N-R⁴ -anilines, which are required as intermediates forthe preparation of the carbonylbenzenedicarboxylic acid intermediates ofFormulas III and IV wherein Y represents dialkylaminophenyl, form an oldand well-known class of compounds which are readily obtained byconventional procedures well known in the art. The following compoundsare exemplary of 3-R⁵ -N-R³ -N-R⁴ -anilines useful in the practice ofthis invention.

N,N-Dibutylaniline,

N,N-Diethyl-3-ethoxyaniline,

N,N-Diethyl-m-anisidine,

N,N-Dimethylaniline,

N-Benzyl-N-ethylaniline,

N,N-Diethyl-m-toluidine,

N,N-Diethylaniline,

N-Ethyl-N-methylaniline,

N-Benzyl-N-methylaniline,

N-Benzyl-N-propylaniline,

N,N-Dimethyl-3-bromoaniline,

N,N-Dibutyl-3-fluoroaniline,

N-Benzyl-N-methyl-3-ethylaniline,

N-Benzyl-3-butyl-3-iodoaniline,

N,N-Diisopropyl-3-chloroaniline,

N-Benzyl-N-sec-butylaniline,

N-N-Dipropylaniline,

N-Isopropyl-N-methylaniline,

N-Methyl-N-propylaniline,

N,N-Di-sec-butylaniline,

N,N-Diethyl-3-isopropylaniline,

N,N-Diisobutylaniline,

N,N-Dimethyl-m-toludine,

N-Isobutyl-N-ethylaniline,

N-Propyl-N-ethylaniline,

N-(4-Chlorobenzyl)-N-methylaniline,

N-(3-Bromobenzyl)-N-ethylaniline,

N,N-Di(4-methylbenzyl)aniline,

N-(4-Nitrobenzyl)-N-i-propylaniline,

N,N-Di(2,4-dichlorobenzyl)aniline,

N-(2,3-Dimethylbenzyl)-N-methylaniline,

N-(3-Nitrobenzyl)-N-sec-butylaniline.

The N-(R, R°-phenyl)-N-(R¹, R² -phenyl)amines which are required asstarting materials in preparing the isomeric mixtures of pyromellitidesof Formulas I and II of the invention belong to a well known class ofcompounds and are either commercially available or are readily obtainedby conventional procedures well known in the art. The followingcompounds are exemplary of N-(R, R°-phenyl)-N-(R¹, R² -phenyl)aminesuseful in the practice of this invention.

Diphenylamine,

4-Ethoxy-N-phenylaniline,

3-Methyl-N-phenylaniline,

4-Isopropyl-N-phenylaniline,

4-Hydroxy-N-phenylaniline,

4,4'-Dioctyldiphenylamine,

3,3'-Diethyl-5,5'-dinonyldiphenylamine,

3-Chloro-N-phenylaniline,

4-Dimethylamino-N-phenylaniline,

Methyl-2-anilinobenzoate,

4,4'-Bis(dimethylamino)diphenylamine,

4-Acetamido-N-phenylaniline,

4,4'-Diacetamidodiphenylamine,

4-Octyl-4'-arylalkyldiphenylamine,

4,4'-Bis(diethylamino)diphenylamine,

4-Diethylamino-4'-dimethylaminodiphenylamine,

(4-Toluenesulfonamido)aniline.

The molecular structure of the compounds were assigned on the basis ofthe modes of synthesis and a study of their infrared and nuclearmagnetic spectra.

The following examples will further illustrate the invention without,however, limiting it thereto.

EXAMPLE 1

A. A mixture of 6.4 g of pyromellitic dianhydride, 9.0 g of1-ethyl-2-methylindole and 80.0 ml of toluene was stirred and cooled bymeans of an external ice-water bath to a temperature in the range of0°-5° C. Over approximately ten minutes, 8.8 g of anhydrous aluminumchloride was added to the mixture while maintaining the temperature at0°-5° C. After stirring approximately ten minutes at 0°-5° C., thereaction mixture was warmed to 45°-55° C. and stirring continued for anadditional thirty minutes. To the reaction mixture there was added 5.0ml of acetic anhydride and the mixture was stirred approximately thirtyminutes at a temperature in the range of 50°-60° C. While maintaining atemperature in the range of 50°-60° C., 50.0 ml ofconcentratedhydrochloric acid diluted with 150.0 ml of water was added to thereaction mixture. Without cooling, the solid, which separated, wascollected by filtration and washed with 50.0 ml of water. The water-wetfilter cake was suspended in 50.0 ml of water with stirring andsufficient concentrated ammonium hydroxide was added gradually until thepH of the mixture was 10.0. The undissolved solid was removed byfiltration and the filtrate was treated with decolorizing carbon and theresultant mixture filtered to remove the carbon. The filtrate wasadjusted to pH 2.5 by the addition of three normal hydrochloric acid.The solid which formed was collected by filtration, washed with waterand dried to obtain an isomeric mixture of[2,4-bis(1-ethyl-2-methylindol-3-yl)carbonyl]-1,5-benzenedicarboxylicacid (Formula III: Y=1-C₂ H₅ -2-CH₃ -indol-3-yl) and[2,5-bis(1-ethyl-2-methylindol-3-yl)carbonyl]-1,4-benzenedicarboxylicacid (Formula IV: Y=1-C₂ H₅ -2-CH₃ -indol-3-yl).

B. A mixture containing 1.0 g of the isomeric mixture[2,4-bis(1-ethyl-2-methylindol-3-yl)carbonyl]-1,5-benzenedicarboxylicacid and[2,5-bis(1-ethyl-2-methylindol-3-yl)carbonyl]-1,4-benzenedicarboxylicacid, from part A above, 2.2 g of di(4-octylphenyl)amine and 6.0 ml ofacetic anhydride was stirred at a temperature in the range of 45°-550°C. for approximately thirty minutes. The reaction mixture was placed ina freezer for approximately fifteen minutes. After removing from thefreezer, a red solid material was collected by filtration and thefiltrate was added with stirring to approximately 25.0 ml water causingan oily red solid to agglomerate. The desired product was separated fromthe starting materials using a chromatographic column packed with 40-140mesh silica gel employing isopropyl alcohol to elute the desired productthrough the column followed by a hexane wash of the column. The combinedisopropyl alcohol and hexane mixture containing the desired product wasevaporated to dryness to obtain a red-orange oil. The oil was dissolvedin methyl alcohol and a trace of insolubles removed by filtration. Themethanol solution was allowed to evaporate to dryness by standing atambient temperature over a weekend to obtain 0.5 g of an isomericmixture of3,7-bis(1-ethyl-2-methylindol-3-yl)-3,7-bis[N,N-di(4-octylphenyl)-amino]pyromellitide(Formula I: R=R¹ =4-C₈ H₁₇ ; R^(o) =R² =H; Y=2-C₂ H₅ -2-CH₃ -indol-3-yl)and3,5-bis(1-ethyl-2-methylindol-3-yl)-3,5-bis[N,N-di(4-octylphenyl)amino]pyromellitide(Formula II: R=R¹ =4-C₈ H₁₇ ; R^(o) =R² =H; Y=1-C₂ H₅ -2CH₃ -CH₃-indol-3-yl), an orange-red solid, which melted over the range 83°-92°C. The nuclear magnetic resonance spectrum was in accord with theassigned structure. An infrared maximum appeared at 1781 (C═O; s) cm⁻¹.A toluene solution of the product spotted on an acidic clay or aphenolic resin developed an orange-colored image.

EXAMPLE 2

A mixture containing 6.5 g of the isomeric mixture of[2,4-bis(1-ethyl-2-methylindol-3-yl)carbonyl]-1,5-benzenedicarboxylicacid and[2,5-bis(1-ethyl-2-methylindol-3-yl)carbonyl]-1,4-benzenedicarboxylicacid prepared in a manner similar to that described in Example 1, part Aabove, 20.0 ml of acetic anhydride, 5.0 ml of acetic acid and 4.7 g ofdiphenylamine was stirred for approximately 48 hours at ambienttemperature. The solid that formed was collected by filtration, washedwith isopropyl alcohol and dried to obtain 4.6 g of a pink-coloredsolid. This solid was reslurried twice in hot isopropyl alcohol,filtered and dried to obtain 3.7 g of an isomeric mixture of3,7-bis(1-ethyl-2-methylindol-3-yl)-3,7-bis(diphenylamino)-pyromellitide(Formula I: R=R^(o) =R¹ =R² =H; Y=1-C₂ H₅ -2-CH₃ -indol-3-yl) and3,5-bis(1-ethyl-2-methylindol-3-yl)-3,5-bis(diphenylamino)pyromellitide(Formula II: R=R^(o) =R¹ =R² =H; Y=1-C₂ H₅ -2-CH₃ -indol-3-yl), a palepink-colored solid, which melted at 235°-238° C. The nuclear magneticresonance spectrum was in accordance with the assigned structure. Amaximum appeared in the infrared spectrum at 1770 (C═O; s) cm⁻¹. Atoluene solution of the product spotted on an acidic clay phenolic resindeveloped an orange-colored image.

EXAMPLE 3

A mixture of 5.4 g of an isomeric mixture of2,4-bis[(1-ethyl-2-methylindol-3-yl)carbonyl]-1,5-benzenedicarboxylicacid and2,5-bis[(1-ethyl-2-methylindol-3-yl)carbonyl]-1,4-benzenedicarboxylicacid, prepared in a manner similar to that described in Example 1, partA above, 4.3 g of N-(4-ethoxyphenyl)aniline, 10.0 ml of acetic aceticanhydride and 2.0 ml of pyridine was stirred approximately one hour atambient temperature. Slowly, 20.0 ml of isopropyl alcohol and 30.0 ml ofligroin were added to the mixture. A gummy product which separated wascollected by decantation, and recrystallized from isopropyl alcohol toobtain 2.3 g of the isomeric mixture of3,7-bis(1-ethyl-2-methylindol-3-yl)-3,7-bis(N-4-ethoxyphenyl-N-phenyl)-aminopyromellitide (Formula I: R=4-C₂ H₅ O; R^(o) =R¹ =R² =H; Y=1-C₂ H₅-2-CH₃ -indol-3-yl) and3,5-bis-(1-ethyl-2-methylindol-3-yl)-3,5-bis(N-4-ethoxyphenyl-N-phenyl)aminopyromellitide (Formula II: R= 4-C₂ H₅ O; R^(o) =R¹ =R² =H; Y-1-C₂ H₅-2-CH₃ -indol-3-yl), a light brown solid, which melted 157°-160° C. Asignificant infrared maximum appeared at 1760 (C═O; s) cm⁻¹. A toluenesolution of the product spotted on an acidic clay or a phenolic resindeveloped a brown-colored image.

EXAMPLE 4

A. Proceeding in a manner similar to that described in Example 1, part Aabove. 10.9 g of pyromellitic dianhydride and 24.2 g ofN,N-dimethylaniline were interacted in the presence of 13.3 g ofanhydrous aluminum chloride in 40.0 ml chlorobenzene to obtain 3.1 g ofthe isomeric mixture of2,4-bis[(4-dimethylaminophenyl)carbonyl]-1,5-benzenedicarboxylic acid(Formula III: Y=4-(CH₃)₂ NC₆ H₅) and2,5-bis[(4-dimethylaminophenyl)carbonyl]-1,4-benzenedicarboxylic acid(Formula IV: 4-(CH₃)₂ NC₆ H₅), a yellow solid, which melted at 273°-276°C.

B. A mixture of 0.23 g of the isomeric mixture of[2,4-bis(4-dimethylaminophenyl)carbonyl]-1,5-benzenedicarboxylic acidand [2,5-bis(4-dimethylaminophenyl)carbonyl]-1,4-benzenedicarboxylicacid from part A above, 0.4 g of di(4-octylphenyl)-amine and 0.3 ml ofacetic anhydride was agitated at a temperature in the range of 40°-45°C. for approximately two hours and sat overnight at ambient temperature.The resulting solid was collected by filtration, washed with hexane anddried to obtain 0.39 g of an isomeric mixture of3,7-bis(4-dimethylaminophenyl)-3,7-bis[N,N-di(4-octylphenyl)amino]pyromellitide(Formula I: R=R¹ =4-C₈ H₁₇ ; R^(o) =R² =H; Y=4-(CH₃)₂ NC₆ H₅) and3,5-bis(4-dimethylaminophenyl)-3,5-bis[N,N-di(4-octylphenyl)amino]-pyromellitide(Formula II: R=R¹ =4-C₈ H₁₇ ; R^(o) =R² =H; Y=4-(CH₃)₂ NC₆ H₅), a paleyellow solid, which melted at 195°- 197° C. A significant infraredmaximum appeared at 1760 (C═O; s) cm⁻¹. An ultraviolet maximum appearedat 255 millimicrons. A toluene solution of the product spotted on anacidic clay or a phenolic resin developed a red-orange image.

EXAMPLE 5

Following a procedure similar to that described in Example 4, part B,0.92 g of an isomeric mixture of[2,4-bis(4-dimethylaminophenyl)carbonyl]-1,5-benzenedicarboxylic acidand [2,5-bis(4-dimethylaminophenyl)carbonyl]1,4-benzenedicarboxylicacid, 0.72 g diphenylamine were interacted in 8.0 ml of acetic anhydrideto obtain 1.1 g of an isomeric mixture of3,7-bis(4-dimethylaminophenyl)-3,7-bis(diphenylamino)pyromellitide(Formula I: R=R^(o) =R¹ =R² =H; Y=4-(CH₃)₂ NC₆ H₅) and3,5-bis(4-dimethylaminophenyl)-3,5-bis(diphenylamino)pyromellitide(Formula II: R=R^(o) =R¹ =R² =H; Y=4(CH₃)₂ NC₆ H₅) which melted at196°-199° C. (dec.). The nuclear magnetic resonance spectrum consistentwith the assigned structure. An infrared maximum appeared at 1770 (C═O;s) cm⁻¹. An ultraviolet maxima appeared at 237 millimicrons. A toluenesolution of the product spotted on an acidic cly or phenolic resindeveloped an orange-colored image.

EXAMPLE 6

A. Proceeding in a manner similar to that described in Example 1, part Aabove, 9.0 g of N,N-diethylaniline and 5.5 g of pyromellitic dianhydridewere interacted in 100.0 ml of toluene in the presence of 16.0 g ofanhydrous aluminum chloride to obtain an isomeric mixture of[2,4-bis(4-diethylaminophenyl)-carbonyl]-1,5-benzenedicarboxylic acid(Formula III: Y=4-(C₂ H₅)₂ NC₆ H₅) and[2,4-bis(4-diethylaminophenyl)carbonyl]-1,5-benzenedicarboxylic acid(Formula IV: Y=4(C₂ H₅)₂ NC₆ H₅), a yellow solid.

B. In amanner similar to that described in Example 4, part B above, amixture of 0.49 g of an isomeric mixture of[2,4-bis(4-diethylaminophenyl)carbonyl]-1,5-benzenedicarboxylic acid and[2,5-bis(4-diethylaminophenyl)carbonyl]-1,4-benzenedicarboxylic acidfrom part A above and 0.80 g di(4-octylphenyl)amine was interacted in4.0 ml of acetic anhydride at 45°-50° C. to obtain 1.0 g of an isomericmixture of3,7-bis(4-diethylaminophenyl)-3,7-bis[N,N-di(4-octylphenyl)amino]pyromellitide(Formula I: R=R¹ =4-C₈ H₁₇ ; R^(o) =R² =H; Y=4-(C₂ H₅)₂ NC₆ H₅) and3,5-bis(4-diethylaminophenyl)-3,5-bis[N,N-di(4-octylphenyl)amino]pyromellitide(Formula II: R=R¹ =4-C₈ H₁₇ ; R^(o) =R² =H; Y=4-(C₂ H₅)₂ NC₆ H₅), ared-brown-colored solid, which melted over the range 88°-96° C. Thenuclear magnetic resonance spectrum was concordant with the assignedstructure. An infrared maximum appeared at 1790 (C═O; s) cm⁻¹. Anultrviolet maximum appeared at 241 millimicrons. A toluene solution ofthe product spotted on an acidic clay or phenolic resin developed anorange-colored image.

EXAMPLE 7

Following a procedure similar to that described in Example 6, part Babove, but substituting 0.34 g of diphenylamine for 0.80 g ofdi(4-octylphenyl)amine, there was obtained 0.3 g of an isomeric mixtureof 3,7-bis(4-diethylaminophenyl)-3,7-bis(diphenylamino)pyromellitide(Formula I: R=R^(o) =R¹ =R² =H; Y=4-(C₂ H₅)₂ NC₆ H₅) and3,5-bis(4-diethylaminophenyl)-3,5-bis(diphenylamino)pyromellitide(Formula II: R=R^(o) =R¹ =R² =H; Y=4-(C₂ H₅)₂ NC₆ H₅), an orange-coloredsolid, which melted over the range of 135°-142° C. The nuclear magneticresonance spectrum was in agreement with the assigned structure. Aninfrared maximum appeared at 1760 (C═O; s) cm⁻¹. The ultraviolet maximumappeared at 271 millimicrons. A toluene solution of the product spottedon an acidic clay or phenolic resin developed an orange-colored image.

EXAMPLE 8

Proceeding in a manner similar to that described in Example 6, part Babove, 0.5 g of an isomeric mixture of2,4-[bis(4-diethylaminophenyl)carbonyl]-1,5-benzenedicarboxylic acid and2,5-[bis(4-diethylaminophenyl)carbonyl]1,4-benzenedicarboxylic acid and0.28 g of N-(3-chlorophenyl)aniline were interacted in 2.0 ml of aceticanhydride to obtain ob 1.0 g of an isomeric mixture of3,7-bis(4-diethylaminophenyl)-3,7-bis[N-3-chlorophenyl-N-phenyl)amino]pyromellitide(Formula I: R=3-Cl; R^(o) =R¹ =R² =H; Y=4-(C₂ H₅)₂ NC₆ H₅) and3,5-bis(4-diethylaminophenyl)-3,5-bis[(N-3-chlorophenyl-N-phenyl)amino]pryromellitide(Formula II: R=3-Cl; R^(o) =R¹ =R² =H; Y=4-(C₂ H₅)₂ NC₆ H₅), anorange-colored solid, which melted over the range of 157°-173° C. Aninfrared maximum appeared at 1765 (C═O; s) cm⁻¹. An ultraviolet maximumappeared at 271 millimicrons. A toluene solution of the product spottedon an acidic clay or phenolic resin developed on orange-colored solid.

It is contemplated that by following the procedure described in Example1, part A above, but using in place of 1-ethyl-2-methylindole theappropriate 1R⁶ -2-R⁷ -indole there will be obtained the followingbenzenedicarboxylic acids, 2,5-bis(1-R⁶ -2-R⁷-indol-3-yl)carbonyl-1,4-benzenedicarboxylic acids and 2,4-bis(1-R⁶-2-R⁷ -indol-3-yl)carbonyl-1,5-benzenedicarboxylic acids and mixturesthereof of Formulas III and IV wherein Y is 1-R⁶ -2-R⁷ -indol-3-yldescribed in Table A hereinbelow.

                  TABLE A                                                         ______________________________________                                        Bis(indolylcarbonyl)benzenedicarboxylic Acids                                  ##STR10##                                                                    and                                                                            ##STR11##                                                                    Example        R.sup.6      R.sup.7                                           ______________________________________                                         9             H            H                                                 10             CH.sub.3     H                                                 11             n-C.sub.4 H.sub.9                                                                          CH.sub.3                                          12             H            CH.sub.3                                          13             n-C.sub.18 H.sub.17                                                                        CH.sub.3                                          14             H            C.sub.6 H.sub.5                                   15             CH.sub.3     CH.sub. 3                                         16             H            C.sub.2 H.sub.5                                   17             i-C.sub.3 H.sub.7                                                                          H                                                 18             CH.sub.3     C.sub.2 H.sub.5                                   19             n-C.sub.6 H.sub.13                                                                         H                                                 20             n-C.sub.12 H.sub.25                                                                        CH.sub.3                                          21             H            i-C.sub.3 H.sub.7                                 22             i-C.sub.5 H.sub.11                                                                         H                                                 23             1-i-C.sub.8 H.sub.17                                                                       CH.sub.3                                          ______________________________________                                    

It is contemplated that by following the procedure described in Example4, part A above, but using in place of N,N-dimethylaniline theappropriate 3-R⁵ -N-R³ -N-R⁴ -aniline there will be obtained thefollowing benezenedicarboxylic acids selected from the group consistingof 2,5-bis(2-R⁵ -4-NR³ R⁴ -phenyl)carbonyl-1,4-benezenedicarboxylicacids and 2,4-bis(2-R⁵ -4-NR³ R⁴-phenyl)carbonyl-1,5-benzenedicarboxylic acids and mixtures thereof ofFormulas III and IV wherein Y is 2-R⁵ 4-NR³ R⁴ -phenyl described inTable B hereinbelow.

                  TABLE B                                                         ______________________________________                                        Bis[(disubstituted aminophenyl)carbonyl]-                                     benzenedicarboxylic Acids                                                      ##STR12##                                                                    and                                                                            ##STR13##                                                                    Example    R.sup.3       R.sup.4   R.sup.5                                    ______________________________________                                        24         n-C.sub.4 H.sub.9                                                                           n-C.sub.4 H.sub.9                                                                       H                                          25         C.sub.2 H.sub.5                                                                             C.sub.2 H.sub.5                                                                         OC.sub.2 H.sub.5                           26         C.sub.6 H.sub.5 CH.sub.2                                                                    C.sub.2 H.sub.5                                                                         H                                          27         C.sub.2 H.sub.5                                                                             C.sub.2 H.sub.5                                                                         CH.sub.3                                   28         C.sub.2 H.sub.5                                                                             C.sub.2 H.sub.5                                                                         OCH.sub.3                                  29         CH.sub.3      CH.sub.3  Br                                         30         n-C.sub.4 H.sub.9                                                                           n-C.sub.4 H.sub.9                                                                       F                                          31         4-ClC.sub.6 H.sub.4 CH.sub.2                                                                CH.sub.3  C.sub.2 H.sub.5                            32         i-C.sub.3 H.sub.7                                                                           i-C.sub.3 H.sub.7                                                                       Cl                                         33         3-CH.sub.3 C.sub.6 H.sub.4 CH.sub.2                                                         s-C.sub.4 H.sub.9                                                                       H                                          34         C.sub.2 H.sub.5                                                                             C.sub.2 H.sub.5                                                                         i-C.sub.3 H.sub.7                          35         i-C.sub.3 H.sub.7                                                                           CH.sub.3  H                                          36         s-C.sub.4 H.sub.9                                                                           s-C.sub.4 H.sub.9                                                                       H                                          37         n-C.sub.3 H.sub.7                                                                           C.sub.2 H.sub.5                                                                         H                                          ______________________________________                                    

It is contemplated that by following the procedure described in theforegoing examples but employing the appropriate benezenedicarboxylicacids of Formulas III and IV and mixtures thereof and the appropriatesubstituted diphenylamine of Formula V there will be obtainedpyromellitides selected from the group consisting of3,7-bis(Y)-3,7-bis[N-(R,R^(o) phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide and 3,5-bis(Y)-3,5-bis[N-(R, R^(o)-phenyl)-N-(R¹, R² -phenyl)amino]pyromellitide and mixtures thereof ofFormulas I and II, Examples 37-65, presented in Table C hereinbelow.

                                      TABLE C                                     __________________________________________________________________________    Pyromellitides of Formulas I and II                                            ##STR14##                                                                    Example    Y                 R           R.sup.o                                                                              R.sup.1 R.sup.2               __________________________________________________________________________    38      indol-3-yl           H           3-CH.sub.3                                                                           H       H                     39      1-methylindol-3-yl   4-i-C.sub.3 H.sub.7                                                                       H      H       H                     40      1-n-butyl-2-methylindol-3-yl                                                                       4-OH        H      H       H                     41      2-methylindol-3-yl   5-C.sub.9 H.sub.19                                                                        3-C.sub.2 H.sub.5                                                                    5-C.sub.9 H.sub.19                                                                    3-C.sub.2                                                                     H.sub.5               42      1-n-octyl-2-methylindol-3-yl                                                                       H           3-Cl   H       H                     43      2-phenylindol-3-yl   4-(CH.sub.3).sub.2 N                                                                      H      H       H                     44      1,2-dimethylindol-3-yl                                                                             H           2-COOCH.sub.3                                                                        H       H                     45      2-ethylindol-3-yl    4-(CH.sub.3).sub.2 N                                                                      H      4-(CH.sub.3).sub.2                                                                    H                     46      1-i-propylindol-3-yl 4-CH.sub.3 CONH                                                                           H      H       H                     47      1-methyl-2-ethylindol-3-yl                                                                         4-CH.sub.3 CONH                                                                           H      4-CH.sub.3 CONH                                                                       H                     48      1-n-hexylindol-3-yl  4-(C.sub.2 H.sub.5).sub.2 N                                                               H      4-(C.sub.2 H.sub.5).sub.2                                                     N       H                     49      1-n-dodecyl-2-methylindol-3-yl                                                                     4-(C.sub.2 H.sub.5).sub.2 N                                                               H      4-(CH.sub.3).sub.2                                                                    H                     50      2-i-propylindol-3-yl H           2-C.sub.2 H.sub.5                                                                    H       H                     51      1-i-amylindol-3-yl   H           3-I    H       H                     52      1-i-octyl-2-methylindol-3-yl                                                                       4-Br        H      H       H                     53      4-di-n-butylaminophenyl                                                                            H           2-CH.sub.3                                                                           4-CH.sub.3 O                                                                          H                     54      2-ethoxy-4-diethylaminophenyl                                                                      H           3-Br   5-Br    H                     55      4-Nbenzyl-Nethylaminophenyl                                                                        H           2-F    H       H                     56      2-methyl-4-diethylaminophenyl                                                                      H           2-Cl   4-F     H                     57      2-methoxy-4-diethylaminophenyl                                                                     H           3-CH.sub.3 O                                                                         H       3-CH.sub.3 O          58      2-bromo-4-dimethylaminophenyl                                                                      4-CH.sub.3  2-CH.sub.3                                                                           4-CH.sub.3                                                                            3-CH.sub.3            59      2-fluoro-4-di-n-butylaminophenyl                                                                   H           4-n-C.sub.4 H.sub.9 O                                                                H       4-n-C.sub.4                                                                   H.sub.9 O             60      2-ethyl-4-N(4-chlorobenzyl)-                                                                       4-Cl        2-Cl   4-Cl    2-Cl                          Nmethylaminophenyl                                                    61      2-chloro-4-di-i-propylaminophenyl                                                                  4-n-C.sub.6 H.sub.13                                                                      H      H       H                     62      4-N(3-methylbenzyl)-Ns-butyl-                                                                      4-NHSO.sub.2 C.sub.6 H.sub.5                                                              H      H       H                             aminophenyl                                                           63      2-i-propyl-4-diethylaminophenyl                                                                    4-NHSO.sub.2 (4-CH.sub.3 C.sub.6 H.sub.4)                                                 H      H       H                     64      4-Nmethyl-Ni-propylaminophenyl                                                                     4-NH.sub.2  H      4-NH.sub.2                                                                            H                     65      4-di-s-butylaminophenyl                                                                            4-NHC.sub.6 H.sub.11                                                                      H      H       H                     66      4-Nethyl-Npropylaminophenyl                                                                        4-NHC.sub.4 H.sub.9                                                                       H      4-NHC.sub.4 H.sub.9                                                                   H                     __________________________________________________________________________

EXAMPLE 67

The use of the pyromellitide compounds of Formulas I and II anddescribed in Examples 1 through 8 and 37 through 65 as color formingcomponents in pressure-sensitive microencapsulated copying system isillustrated with reference to the product of Example 2.

A. A mixture of 60.0 ml of distilled water and 7.5 g of pigskin gelatinwas stirred at approximately 50° C. for approximately one hour. Therewas added to the mixture a warmed (approximately 50° C.) solution of30.0 g of alkylated biphenyls and 0.73 g of an isomeric mixture of3,7-bis(1-ethyl-2-methylindol-3-yl)-3,7-bis(diphenylamino)pyromellitideand3,5-bis(1-ethyl-2-methylindol-3-yl)-3,5-bis(diphenylamino)pyromellitideprepared as described above in Example 2. The resulting solution wasstirred for approximately two minutes. A second solution of 100.0 ml ofdistilled water and 2.5 g of carboxymethylcellulose was prepared andwarmed to approximately 50° C. for approximately one hour.

B. The two solutions, the first containing water, gelatin, alkylatedbiphenyls and the product, and the second containing water withcarboxymethylcellulose were mixed by means of an Eppenbach Homo-Mixer(Gifford-Wood Co., Hudson, N.Y.). The pH was adjusted to 6.5 by theaddition of approximately 0.7 ml of 5 percent aqueous sodium hydroxide.To the resultant mixture 335.0 ml of distilled water which had beenheated to 50° C. was added over a period of two to three minutes. Withthe stirrer running at an applied voltage of between 35 to 40 voltsthere was added sufficient ten percent aqueous acetic acid to set the pHat 4.5, this being the point where coacervation was initialed. Afterapproximately five minutes, an external ice-water bath was placed aroundthe reactor containing the suspension. Cooling was continued and atapproximately 15° C., 5.0 ml of glutaraldehyde was added over a periodof five minutes. When the internal temperature reached 10° C., theEppenback Homo-Mixer was replaced with a conventional blade typelaboratory agitator and the thus prepared suspension of microcapsuleswas stirred overnight during which period of time the temperature wasallowed to warm to room temperature. In the morning 4.0 g of water wasadded and stirring continued for a combined total of 24 hours.

C. The microcapsule suspension prepared as described in part B above wascoated on paper sheets to a thickness of approximately 0.0015 inch andthe coated paper air dried. The paper thus coated with themicroencapsulated colorless precursor was assembled as the top sheet ina manifold system by positioning the coated side in contact with thecoated side of a commercially available receiving sheet coated with acolor developer of the electron accepting type. More specifically,papers coated with a phenolic resin and with an acidic clay wereemployed in this test. An image was then drawn with a stylus on the topsheet bearing the microencapsulated colorless precursor on its reverseside causing the affected microcapsules to rupture thus allowing thesolution of the colorless precursor held by said microcapsules to flowinto contact with the color developing substance on the receiving sheetwhereupon a deep orange-colored image promptly formed.

EXAMPLE 68

The utility of the pyromellitides of Formulas I and II whosepreparations are described in the foregoing examples as color formingcomponents in thermal marking systems is illustrated by theincorporation and testing of the compounds of Example 2, in a thermalsensitive marking paper. The test paper was prepared by a proceduresimilar to that described in U.S. Pat. No. 3,539,375.

A. A mixture of 2.0 g of an isomeric mixture of3,7-bis(1-ethyl-2-methylindol-3-yl)-3,7-bis(diphenylamino)pyromellitideand3,5-bis(1-ethyl-2-methylindol-3-yl)-3,5-bis(diphenylamino)pyromellitideprepared as described in Example 2, 8.6 g of a ten percent aqueoussolution of polyvinyl alcohol (approximately 99 percent hydrolyzed), 3.7g of water and 31.6 g of 1/16 inch diameter zirconium grinding beads wascharged into a container which was placed in a mechanical shaker.Shaking was effected for one hour and the zirconium beads were removedby straining the mixture through a No. 40 sieve.

B. Similarly, a mixture of 9.8 g of 4,4'-isopropylidine diphenol(Bisphenol A), 42.0 g of a ten percent aqueous polyvinyl alcoholsolution (approximately 99 percent hydrolyzed), 18.2 g of water and221.2 g of 1/16 inch diameter zirconium grinding beads was charged intoa container which was placed in a mechanical shaker. After shaking waseffected for one hour, the zirconium beads were removed by strainingthrough a No. 40 sieve.

C. A coating composition was prepared by mixing 2.1 g of the slurry frompart A above and 47.9 g of the slurry from part B above. The mixture wasuniformly coated on sheets of paper at thicknesses of approximately0.0015 inch and the coated sheets air-dried. The coated paper was testedby tracing a design on the coated side of the paper placed on a smoothflat surface with a stylus heated to approximately 125° C. A deeporange-colored image corresponding to the traced design promptlydeveloped.

What is claimed is:
 1. A compound selected from the group consisting of3,7-bis(Y)-3,7-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide having the formula ##STR15## and3,5-bis(Y)-3,5-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide having the formula ##STR16## and mixturesthereof wherein: R, R^(o), R¹ and R² are the same or different and areselected from the group consisting of hydrogen, halo, hydroxyl, C₁ to C₄alkoxy, non-tertiary C₁ to C₉ alkyl, COOZ and NZ¹ Z² where Z and Z¹ arehydrogen or non-tertiary C₁ to C₄ alkyl and Z² is hydrogen, non-tertiaryC₁ to C₄ alkyl, C₅ to C₇ cycloalkyl, C₁ to C₄ alkanoyl, phenylsulfonylor phenylsulfonyl substituted by non-tertiary C₁ to C₄ alkyl;Y is aradical selected from the group consisting of ##STR17## in which R³ andR⁴ are the same or different and are selected from the group consistingof non-tertiary C₁ to C₄ alkyl, benzyl, and benzyl substituted by one ortwo of halo, C₁ to C₄ alkyl, C₁ to C₄ alkoxy or nitro; R⁵ is selectedfrom the group consisting of hydrogen, non-tertiary C₁ to C₄ alkyl, haloand C₁ to C₄ alkoxy; R⁶ is selected from the group consisting ofhydrogen and non-tertiary C₁ to C₁₂ alkyl; and R⁷ is selected from thegroup consisting of hydrogen, non-tertiary C₁ to C₄ alkyl and phenyl. 2.A compound selected from the group consisting of 3,7-bis(1-R⁶ -2-R⁷-indol-3-yl)-3,7-[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide and 3,5-bis(1-R⁶ -2-R⁷-indol-3-yl)3,5-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide and mixtures thereof according to claim 1wherein Y represents 1-R⁶ -2-R⁷ -indol-3-yl and R, R^(o), R¹, R², R⁶ andR⁷ each have the same respective meanings given in claim
 1. 3.3,7-Bis(1-ethyl-2-methylindol-3-yl)-3,7-bis[N-phenyl-N-(4-ethoxyphenyl)amino]pyromellitideaccording to claim
 2. 4.3,5-Bis(1-ethyl-2-methylindol-3-yl)-3,5-bis[N-phenyl-N-(4-ethoxyphenyl)amino]pyromellitideaccording to claim
 2. 5.3,7-Bis(1-ethyl-2-methylindol-3-yl)-3,7-bis[di(4-octylphenyl)amino]pyromellitideaccording to claim
 2. 6.3,5-Bis(1-ethyl-2-methylindol-3-yl)-3,5-bis[di(4-octylphenyl)amino]pyromellitideaccording to claim
 2. 7.3,7-Bis(1-ethyl-2-methylindol-3-yl)-3,7-bis(diphenylamino)pyromellitideaccording to claim
 2. 8.3,5-Bis(1-ethyl-2-methylindol-3-yl)-3,5-bis(diphenylamino)pyromellitideaccording to claim
 2. 9. A compound selected from the group consistingof 3,7-bis(2-R⁵ -4-NR³ R⁴ -phenyl)-3,7-bis[N-(R, R^(o) -phenyl)-N-(R¹,R² -phenyl)amino]pyromellitide and 3,5-bis(2-R⁵ -4-NR³ R⁴phenyl)-3,5-bis[N-(R, R^(o) -phenyl)-N-(R¹, R²-phenyl)amino]pyromellitide according to claim 1 wherein Y represents2-R⁵ -4NR³ R⁴ -phenyl and R, R^(o), R¹, R², R³, R⁴ and R⁵ each have thesame respective meanings given in claim
 1. 10.3,7-Bis(4-dimethylaminophenyl)-3,7-bis[di(4-octylphenyl)amino]pyromellitideaccording to claim
 9. 11.3,5-Bis(4-dimethylaminophenyl)-3,5-bis[di(4-octylphenyl)amino]pyromellitideaccording to claim
 9. 12.3,7-Bis(4-dimethylaminophenyl)-3,7-bis(diphenylamino)pyromellitideaccording to claim
 9. 13.3,5-Bis(4-dimethylaminophenyl)-3,5-bis(diphenylamino)pyromellitideaccording to claim
 9. 14.3,7-Bis(4-diethylaminophenyl)-3,7-bis[di(4-octylphenyl)amino]pyromellitideaccording to claim
 9. 15.3,5-Bis(4-diethylaminophenyl)-3,5-bis[di(4-octylphenyl)amino]pyromellitideaccording to claim
 9. 16.3,7-Bis(4-diethylaminophenyl)-3,7-bis(diphenylamino)pyromellitideaccording to claim
 9. 17.3,5-Bis(4-diethylaminophenyl)-3,5-bis(diphenylamino)pyromellitideaccording to claim
 9. 18.3,7-Bis(4-diethylaminophenyl)-3,7-bis[N-(4-chlorophenyl)-N-phenylamino]pyromellitideaccording to claim
 9. 19.3,5-Bis(4-diethylaminophenyl)-3,5-bis[N-(4-chlorophenyl)-N-phenylamino]pyromellitideaccording to claim 9.